Submission #125686

#	Time	Username	Problem	Language	Result	Execution time	Memory
125686		EntityIT	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	242 ms	88524 KiB

joi2019_ho_t1

#include<bits/stdc++.h>

using namespace std;

const int N = (int)3e3 + 5;
int n, m, cnt[2][N][N];
char s[N][N];
long long ans;

int main () {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    cin >> n >> m;
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j) cin >> s[i][j];
    }

    for (int i = n; i > 0; --i) {
        for (int j = m; j > 0; --j) {
            cnt[0][i][j] = cnt[0][i][j + 1] + (s[i][j] == 'O');
            cnt[1][i][j] = cnt[1][i + 1][j] + (s[i][j] == 'I');
            if (s[i][j] == 'J') ans += cnt[0][i][j] * cnt[1][i][j];
        }
    }

    cout << ans;

    return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 50 / 50